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Why isn't my seller ID found in the ad system's sellers.json?

Updated Oct 7, 2026 · data from 12 App Store genres · top free + top grossing charts · US · iOS + Android

Short answerEach app-ads.txt line names an account at an ad system. If that account isn't in the ad system's public sellers.json, buyers who validate the supply chain can't match the line to a seller.
642 of 883 ad-monetized top US apps in this index have this finding (73%)

Why it matters

Buyers that check sellers.json may ignore lines they can't match, which can reduce demand for that path.

Common causes are closed accounts, former partners whose lines were never removed, typos in the ID, or an ad system whose sellers.json lists only part of its accounts.

How to fix it

  1. Check the ID character by character against what the partner gave you.
  2. Ask the partner whether the account is still active and request their current lines.
  3. Remove lines for accounts that were closed or partners you no longer work with.

Apps with this finding

Each report lists the exact lines involved.

All apps →

Questions

What if the ad system's sellers.json is incomplete?

When more than half of the IDs apps list for an ad system are missing from its sellers.json, we don't hold those lines against apps; the ad system is shown as "Most listed IDs not found".

Does a missing ID mean the line is fake?

No. It means the public file doesn't confirm it. Old and closed accounts are the most common reason.

Related

Based on the IAB Tech Lab ads.txt/app-ads.txt and sellers.json specifications. Numbers are automated observations of public files on the date above.